Valuable printed matters including securities such as banknotes, stock certificates, and bonds, cards, various kinds of certificates, and important documents require not to be forged or altered as their properties. Examples of preventive measures are printing using special ink, hologram, thread, and printing of microletters.
The present applicant has proposed, as one of such preventive measures as described above, an invention of a latent image pattern formed body in which at least one of various kinds of parallel line patterns or relief patterns, which express a motif by partially changing the angle, is printed using raised print image lines, and at least one of various kinds of parallel image lines or halftone dot image lines having a predetermined interval is printed on the print image lines parallelly or obliquely with respect to the print image lines (for example, see patent reference 1).
The present applicant has also proposed another invention of a latent image pattern formed body in which at least one of various kinds of parallel line patterns or relief patterns, which express a motif by partially changing the angle, is printed by embossing to form an uneven material, and at least one of various kinds of parallel image lines or halftone dot image lines having a predetermined interval is printed on the uneven material parallelly or obliquely with respect to a portion that forms a portion other than the uneven motif (for example, see patent reference 2).